What changes occur in elastin in normal development, wigh age, and with disease? What techniques are applicable to the preparation and characterization of the components of the elastin fiber in the lung? How is the elastin linked? What techniques can be adopted to separate elastin from other lung constituants? Can elastin microfibrils be separated from amorphous elastin? Can vascular and other elastin be isolated from each other? Is lung elastin formed from a soluble precursor? What is the nature of the precursor?